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Janus emulsions, containing olive oil (OO) and silicone oil (SiO), were formed in presence of polyelectrolyte complex particles, i.e., gelatin-sodium polyacrylate (NaPAA) complexes. The diameter of completely engulfed Janus droplets can be tuned between 50 and 200 mu m by varying the gelatin/NaPAA complex particle size between 200 and 400 nm. The gelatin/NaPAA complex particles adsorbed at the olive oil interface decrease the interfacial tension and stabilize the resulting completely engulfed Pickering Janus emulsions. Long-term stable Janus gels can be synthesized in presence of gelatin/sodium carboxymethylcellulose (NaCMC) mixtures. In that case Coulombic forces are of relevance with regard to the stabilization of the Janus droplets embedded in a gelatin/NaCMC gel matrix. Janus gels show elastic reological behavior and thixotropic properties.
The amplified spontaneous emission from a superluminescent diode was frequency doubled in a periodically poled lithium niobate waveguide crystal. The temporally incoherent radiation of such a superluminescent diode is characterized by a relatively broad spectral bandwidth and thermal-like photon statistics, as the measured degree of second order coherence, g((2))(0)= 1.9 +/- 0.1, indicates. Despite the non-optimized scenario in the spectral domain, we achieve six orders of magnitude higher conversion efficiency than previously reported with truly incoherent light. This is possible by using single spatial mode radiation and quasi phase matched material with a waveguide architecture. This work is a principle step towards efficient frequency conversion of temporally incoherent radiation in one spatial mode to access wavelengths where no radiation from superluminescent diodes is available, especially with tailored quasi phase matched crystals. The frequency doubled light might find application in imaging, metrology and quantum optics experiments.
This is the first of a series of papers presenting the results from our survey of 25 Galactic globular clusters with the MUSE integral-field spectrograph. In combination with our dedicated algorithm for source deblending, MUSE provides unique multiplex capabilities in crowded stellar fields and allows us to acquire samples of up to 20 000 stars within the half-light radius of each cluster. The present paper focuses on the analysis of the internal dynamics of 22 out of the 25 clusters, using about 500 000 spectra of 200 000 individual stars. Thanks to the large stellar samples per cluster, we are able to perform a detailed analysis of the central rotation and dispersion fields using both radial profiles and two-dimensional maps. The velocity dispersion profiles we derive show a good general agreement with existing radial velocity studies but typically reach closer to the cluster centres. By comparison with proper motion data, we derive or update the dynamical distance estimates to 14 clusters. Compared to previous dynamical distance estimates for 47 Tuc, our value is in much better agreement with other methods. We further find significant (>3 sigma) rotation in the majority (13/22) of our clusters. Our analysis seems to confirm earlier findings of a link between rotation and the ellipticities of globular clusters. In addition, we find a correlation between the strengths of internal rotation and the relaxation times of the clusters, suggesting that the central rotation fields are relics of the cluster formation that are gradually dissipated via two-body relaxation.
Sequelae of prematurity triggered by oxidative stress and free radical-mediated tissue damage have coined the term “oxygen radical disease of prematurity”. Caffeine, a potent free radical scavenger and adenosine receptor antagonist, reduces rates of brain damage in preterm infants. In the present study, we investigated the effects of caffeine on oxidative stress markers, anti-oxidative response, inflammation, redox-sensitive transcription factors, apoptosis, and extracellular matrix following the induction of hyperoxia in neonatal rats. The brain of a rat pups at postnatal Day 6 (P6) corresponds to that of a human fetal brain at 28–32 weeks gestation and the neonatal rat is an ideal model in which to investigate effects of oxidative stress and neuroprotection of caffeine on the developing brain. Six-day-old Wistar rats were pre-treated with caffeine and exposed to 80% oxygen for 24 and 48 h. Caffeine reduced oxidative stress marker (heme oxygenase-1, lipid peroxidation, hydrogen peroxide, and glutamate-cysteine ligase catalytic subunit (GCLC)), promoted anti-oxidative response (superoxide dismutase, peroxiredoxin 1, and sulfiredoxin 1), down-regulated pro-inflammatory cytokines, modulated redox-sensitive transcription factor expression (Nrf2/Keap1, and NFκB), reduced pro-apoptotic effectors (poly (ADP-ribose) polymerase-1 (PARP-1), apoptosis inducing factor (AIF), and caspase-3), and diminished extracellular matrix degeneration (matrix metalloproteinases (MMP) 2, and inhibitor of metalloproteinase (TIMP) 1/2). Our study affirms that caffeine is a pleiotropic neuroprotective drug in the developing brain due to its anti-oxidant, anti-inflammatory, and anti-apoptotic properties.
Entre los mundos
(2017)
The paper deals with the increasing growth of embedded systems and their role within structures similar to the Internet (Internet of Things) as those that provide calculating power and are more or less appropriate for analytical tasks. Faced with the example of a cyber-physical manufacturing system, a common objective function is developed with the intention to measure efficient task processing within analytical infrastructures. A first validation is realized on base of an expert panel.
Despite high institutional hurdles for constitutional change, one observes surprisingly many EU treaty revisions. This article takes up the questions of what determines whether a treaty provision is successfully changed and why provisions are renegotiated at subsequent Intergovernmental Conferences. The article presents an institutionalist theory explaining success and renegotiation and tests the theory using all core institutional provisions by means of Qualitative Comparative Analysis. The causal analysis shows that low conflict potential of an issue is sufficient for successfully changing the treaties. Furthermore, high conflict potential of an issue and its fundamental change are sufficient for it to be renegotiated.
Winter precipitation forecast in the European and mediterranean regions using cluster analysis
(2017)
The European climate is changing under global warming, and especially the Mediterranean region has been identified as a hot spot for climate change with climate models projecting a reduction in winter rainfall and a very pronounced increase in summertime heat waves. These trends are already detectable over the historic period. Hence, it is beneficial to forecast seasonal droughts well in advance so that water managers and stakeholders can prepare to mitigate deleterious impacts. We developed a new cluster-based empirical forecast method to predict precipitation anomalies in winter. This algorithm considers not only the strength but also the pattern of the precursors. We compare our algorithm with dynamic forecast models and a canonical correlation analysis-based prediction method demonstrating that our prediction method performs better in terms of time and pattern correlation in the Mediterranean and European regions.
The past few years have witnessed the emergence of a plethora of transnational climate governance experiments. They have been developed by a broad range of actors, such as cities, non-profit organizations, and private corporations. Several scholars have lately devoted particular attention to voluntary global business initiatives in the policy domain of climate change. Their studies have provided considerable insights into the role and function of such new modes of climate governance. However, the precise nature of the relationship between the various climate governance experiments and the international climate negotiations has not been analyzed in enough detail. Against this backdrop, the present article explores the interplay of a business sector climate governance experiment, i.e. the Greenhouse Gas Protocol (GHG Protocol) with the international climate regime. On the one hand, the article underscores that the GHG Protocol has filled a regulatory gap in global climate policy-making by providing the means for the corporate sector to comprehensively account and report their GHGs. On the other hand, it reveals that the application of the GHG Protocol guidelines depends to a large extent on the existence of an overarching policy framework set up by nation-states at the intergovernmental level. Only if private companies receive a clear political signal that stringent mandatory GHG emission controls and a global market-based instrument are at least likely to be adopted will they put substantial efforts into the accurate measurement and management of their GHGs. Thus, this article points to the limits of climate governance experimentation and suggests that business sector climate governance experiments need to be embedded in a coherent international regulatory setting which generates a clear stimulus for corporate action.
The shape of trait distributions may inform about the selective forces that structure ecological communities. Here, we present a new moment-based approach to classify the shape of observed biomass-weighted trait distributions into normal, peaked, skewed, or bimodal that facilitates spatio-temporal and cross-system comparisons. Our observed phytoplankton trait distributions exhibited substantial variance and were mostly skewed or bimodal rather than normal. Additionally, mean, variance, skewness und kurtosis were strongly correlated. This is in conflict with trait-based aggregate models that often assume normally distributed trait values and small variances. Given these discrepancies between our data and general model assumptions we used the observed trait distributions to test how well different aggregate models with first- or second-order approximations and different types of moment closure predict the biomass, mean trait, and trait variance dynamics using weakly or moderately nonlinear fitness functions. For weakly non-linear fitness functions aggregate models with a second-order approximation and a data-based moment closure that relied on the observed correlations between skewness and mean, and kurtosis and variance predicted biomass and often also mean trait changes fairly well and better than models with first-order approximations or a normal-based moment closure. In contrast, none of the models reflected the changes of the trait variances reliably. Aggregate model performance was often also poor for moderately nonlinear fitness functions. This questions a general applicability of the normal-based approach, in particular for predicting variance dynamics determining the speed of trait changes and maintenance of biodiversity. We evaluate in detail how and why better approximations can be obtained.
Analytic Kantianism
(2017)
Wilfrid Sellars and John McDowell can both be read as proponents of Analytic Kantianism. However, their accounts differ in important detail. In particular, McDowell has criticized Sellars’s account of sensory consciousness in a number of papers (most notably in LFI and SC), both as a reading of Kant and on its systematic merits. The present paper offers a detailed analysis of this criticism and a defense of Sellars’s position against the background of a methodology of transcendental philosophy.
The review describes how morphological priming can be utilised to study the processing of morphologically complex words in bilinguals. The article starts with an overview of established experimental paradigms based on morphological priming, discusses a number of basic methodological pitfalls with regard to experimental design and materials, then reviews previous L2 morphological priming studies, and concludes with a brief discussion of recent developments in the field as well as possible future directions.
BackgroundDisruptions of reading processes due to text substitutions can measure how readers use lexical information. MethodsWith eye-movement recording, children and adults viewed sentences with either identical, orthographically similar, homophonic or unrelated substitutions of the first characters in target words. To the extent that readers rely on orthographic or phonological cues, substitutions that contain such cues should cause less disruption reading than do unrelated substitutions. ResultsOn pretarget words, there was a reliable reduction in gaze duration due to homophonic substitution only for children. On target words, we observed reliable recovery effects due to orthographic similarity for adults. On post-target words, adults had better orthographic-based and phonological-based recovery abilities than children. ConclusionsThe combination of eye movement recording and the error detection paradigm offers a novel implicit paradigm for studying reading development: during sentence reading, beginning readers of Chinese may rely on phonological mediation, while skilled readers have more direct access to semantics from orthography.
Cognitive or executive control is a critical mental ability, an important marker of mental illness, and among the most heritable of neurocognitive traits. Two candidate genes, catechol-O-methyltransferase (COMT) and DRD4, which both have a roles in the regulation of cortical dopamine, have been consistently associated with cognitive control. Here, we predicted that individuals with the COMT Met/Met allele would show improved response execution and inhibition as indexed by event-related potentials in a Go/NoGo task, while individuals with the DRD4 7-repeat allele would show impaired brain activity. We used independent component analysis (ICA) to separate brain source processes contributing to high-density EEG scalp signals recorded during the task. As expected, individuals with the DRD4 7-repeat polymorphism had reduced parietal P3 source and scalp responses to response (Go) compared to those without the 7-repeat. Contrary to our expectation, the COMT homozygous Met allele was associated with a smaller frontal P3 source and scalp response to response-inhibition (NoGo) stimuli, suggesting that while more dopamine in frontal cortical areas has advantages in some tasks, it may also compromise response inhibition function. An interaction effect emerged for P3 source responses to Go stimuli. These were reduced in those with both the 7-repeat DRD4 allele and either the COMT Val/Val or the Met/Met homozygous polymorphisms but not in those with the heterozygous Val/Met polymorphism. This epistatic interaction between DRD4 and COMT replicates findings that too little or too much dopamine impairs cognitive control. The anatomic and functional separated maximally independent cortical EEG sources proved more informative than scalp channel measures for genetic studies of brain function and thus better elucidate the complex mechanisms in psychiatric illness.
The Chelyabinsk meteorite
(2017)
We present results of petrographic, mineralogical, and chemical investigations of three Chelyabinsk meteorite fragments. Three distinct lithologies were identified: light S3LL5, dark S4-S5LL5 material, and opaque fine-grained former impact melt. Olivine-spinel thermometry revealed an equilibration temperature of 703 +/- 23 degrees C for the light lithology. All plagioclase seems to be secondary, showing neither shock-induced fractures nor sulfide-metal veinlets. Feldspathic glass can be observed showing features of extensive melting and, in the dark lithology, as maskelynite, lacking melt features and retaining grain boundaries of former plagioclase. Olivine of the dark lithology shows planar deformation features. Impact melt is dominated by Mg-rich olivine and resembles whole-rock melt. Melt veins (<2mm) are connected to narrower veinlets. Melt vein textures are similar to pegmatite textures showing chilled margins, a zone of inward-grown elongated crystals and central vugs, suggesting crystallization from supercooled melt. Sulfide-metal droplets indicate liquid immiscibility of both silicate and sulfide as well as sulfide and metal melts. Impact melting may have been an important factor for differentiation of primitive planetary bodies. Graphite associated with micrometer-sized melt inclusions in primary olivine was detected by Raman mapping. Carbon isotopic studies of graphite could be applied to test a possible presolar origin.
The uplift of the Shillong Plateau, in northeast India between the Bengal floodplain and the Himalaya Mountains, has had a significant impact on regional precipitation patterns, strain partitioning, and the path of the Brahmaputra River. Today, the plateau receives the highest measured yearly rainfall in the world and is tectonically active, having hosted one of the strongest intra-plate earthquakes ever recorded. Despite the unique tectonic and climatic setting of this prominent landscape feature, its exhumation and surface uplift history are poorly constrained. We collected 14 detrital river sand and 3 bedrock samples from the southern margin of the Shillong Plateau to measure erosion rates using the terrestrial cosmogenic nuclide 10Be. The calculated bedrock erosion rates range from 2.0 to 5.6 m My−1, whereas catchment average erosion rates from detrital river sands range from 48 to 214 m My−1. These rates are surprisingly low in the context of steep, tectonically active slopes and extreme rainfall. Moreover, the highest among these rates, which occur on the low-relief plateau surface, appear to have been affected by anthropogenic land-use change. To determine the onset of surface uplift, we coupled the catchment averaged erosion rates with topographic analyses of the plateau's southern margin. We interpolated an inclined, pre-incision surface from minimally eroded remnants along the valley interfluves and calculated the eroded volume of the valleys carved beneath the surface. The missing volume was then divided by the volume flux derived from the erosion rates to obtain the onset of uplift. The results of this calculation, ranging from 3.0 to 5.0 Ma for individual valleys, are in agreement with several lines of stratigraphic evidence from the Brahmaputra and Bengal basin that constrain the onset of topographic uplift, specifically the onset of flexural loading and the transgression from deltaic to marine deposition. Ultimately, our data corroborate the hypothesis that surface uplift was decoupled from the onset of rapid exhumation, which occurred several millions of years earlier.
To better assess ecosystem C budgets of croplands and understand their potential response to climate and management changes, detailed information on the mechanisms and environmental controls driving the individual C flux components are needed. This accounts in particular for the ecosystem respiration (R-eco) and its components, the autotrophic (R-a) and heterotrophic respiration (R-h) which vary tremendously in time and space. This study presents a method to separate R-eco into R-a [as the sum of R-a (shoot) and R-a (root)] and R-h in order to detect temporal and small-scale spatial dynamics within their relative contribution to overall R-eco. Thus, predominant environmental drivers and underlying mechanisms can be revealed. R-eco was derived during nighttime by automatic chamber CO2 flux measurements on plant covered plots. R-h was derived from CO2 efflux measurements, which were performed in parallel to R-eco measurements on a fallow plot using CO2 sampling tubes in 10 cm soil depth. R-a (root) was calculated as the difference between sampling tube CO2 efflux measurements on a plant covered plot and R-h. R-a (shoot) was calculated as R-eco - R-a (root) - R-h. Measurements were carried out for winter wheat (Triticum aestivum L.) during the crop season 2015 at an experimental plot located in the hummocky ground moraine landscape of NE Germany. R-eco varied seasonally from < 1 to 9.5 g C m(-2) d(-1), and was higher in adult (a) and reproductive (r) than juvenile (j) stands (gC m(-2) d(-1): j = 1.2, a = 4.6, r = 5.3). Observed R-a and R-h were in general smaller compared to the independently measured R-eco, contributing in average 58% and 42% to R-eco. However, both varied strongly regarding their environmental drivers and particular contribution throughout the study period, following the seasonal development of soil temperature and moisture (R-h) as well as crop development (R-a). Thus, our results consistently revealed temporal dynamics regarding the relative contribution of R-a (root) and R-a (shoot) to R-a, as well as of R-a and R-h to R-eco. Based on the observed results, implications for partitioning of R-eco in croplands are given.
Fortsetzung aus Ernährungs Umschau Heft 9/2017
Fettsäurenverteilung
Die Gehalte an den wichtigsten Fettsäuren (FS) sind in • Tabelle 4 und 5 aufgeführt, in g/100 g sowie in Prozent des Fettanteils (Etherextrakt bzw. g FS-Methylester pro 100 g der Summe der FS-Methylester). Erbsen und Ackerbohnen spielen als Fett- und FS-Quelle praktisch keine Rolle. Sojabohnen sind eine wesentliche Quelle für Linolsäure, die häufigste n-6-FS. An zweiter Stelle steht die Ölsäure. Aber auch der Gehalt an der n-3-FS α-Linolensäure (ALA) ist hoch, womit sich Sojaöl in die Reihe der Fette mit mittlerem ALA-Gehalt, wie Raps- und Walnussöl einreiht. Im Gegensatz zu Rapsöl entspricht jedoch das Linolsäure/α-Linolensäure- Verhältnis nicht dem empfohlenen Verhältnis von 5:1 in der Gesamt- Diät [13]. Zum Ausgleich für die Fette aus der übrigen Nahrung (Getreide, Lebensmittel tierischer Herkunft) sollten Pflanzenöle besser noch ein engeres Verhältnis als 5:1 aufweisen. Das trifft für Lupinen-Öl schon eher zu, wenngleich der absolute Beitrag an ALA hier eher gering ist.